The equation of hyperbola $H$ is $\dfrac {(x+3)^{2}}{16}-\dfrac{y^2}{9} = 1$. What are the asymptotes?
We want to rewrite the equation in terms of $y$ , so start off by moving the $y$ terms to one side: $\dfrac{y^2}{9} = - 1 + \dfrac {(x+3)^{2}}{16}$ Multiply both sides of the equation by $9$ $y^2 = { - 9 + \dfrac{ (x+3)^{2} \cdot 9 }{16}}$ Take the square root of both sides. $\sqrt{y^2} = \pm \sqrt { - 9 + \dfrac{ (x+3)^{2} \cdot 9 }{16}}$ $ y = \pm \sqrt { - 9 + \dfrac{ (x+3)^{2} \cdot 9 }{16}}$ As $x$ approaches positive or negative infinity, the constant term in the square root matters less and less, so we can just ignore it. $y \approx \pm \sqrt {\dfrac{ (x+3)^{2} \cdot 9 }{16}}$ $y \approx \pm \left(\dfrac{3 \cdot (x + 3)}{4}\right)$ Rewrite as an equality in terms of $y$ to get the equation of the asymptotes: $y = \pm \dfrac{3}{4}(x + 3)+ 0$